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    <title>ShellCheck: SC2159 – `[ 0 ]` is true. Use `false` instead.</title>
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    <h1>SC2159 – ShellCheck Wiki</h1>
    <a href="https://github.com/koalaman/shellcheck/wiki/SC2159">See this page on GitHub</a>
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    <h2 id="-0--is-true-use-false-instead"><code>[ 0 ]</code> is true. Use
<code>false</code> instead.</h2>
<h3 id="problematic-code">Problematic code:</h3>
<div class="sourceCode" id="cb1"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb1-1"><a href="SC2159.html#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="cf">if</span> <span class="bu">[</span> 0 <span class="bu">]</span></span>
<span id="cb1-2"><a href="SC2159.html#cb1-2" aria-hidden="true" tabindex="-1"></a><span class="cf">then</span></span>
<span id="cb1-3"><a href="SC2159.html#cb1-3" aria-hidden="true" tabindex="-1"></a>  <span class="bu">echo</span> <span class="st">&quot;always triggers&quot;</span></span>
<span id="cb1-4"><a href="SC2159.html#cb1-4" aria-hidden="true" tabindex="-1"></a><span class="cf">fi</span></span></code></pre></div>
<h3 id="correct-code">Correct code:</h3>
<div class="sourceCode" id="cb2"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb2-1"><a href="SC2159.html#cb2-1" aria-hidden="true" tabindex="-1"></a><span class="cf">if</span> <span class="fu">false</span></span>
<span id="cb2-2"><a href="SC2159.html#cb2-2" aria-hidden="true" tabindex="-1"></a><span class="cf">then</span></span>
<span id="cb2-3"><a href="SC2159.html#cb2-3" aria-hidden="true" tabindex="-1"></a>  <span class="bu">echo</span> <span class="st">&quot;never triggers&quot;</span></span>
<span id="cb2-4"><a href="SC2159.html#cb2-4" aria-hidden="true" tabindex="-1"></a><span class="cf">fi</span></span></code></pre></div>
<h3 id="rationale">Rationale:</h3>
<p><code>[ str ]</code> checks whether <code>str</code> is non-empty. It
doesn't matter if <code>str</code> is <code>0</code>, it will still be
evaluated for non-emptyness.</p>
<p>Instead, use the command <code>false</code> which -- as the manual
puts it -- does nothing, unsuccessfully.</p>
<h3 id="exceptions">Exceptions:</h3>
<p>None</p>
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    <p style='font-size: 80%'><a href="../index.html">ShellCheck</a> is a static analysis tool for shell scripts. This page is part of its documentation.</p>
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